This invention relates to the production of arylene sulfide polymer. In one of its aspects this invention relates to the production of arylene sulfide polymer having melt flow in the range of about 1 to about 700 as determined by the method of ASTM D 1238-70. In another of its aspects this invention relates to using a profile of selected temperature ranges in the production of arylene sulfide polymer.
In the use of arylene sulfide polymers in applications such as the production of fibers and molded objects, it is often desirable that the arylene sulfide polymer be of lower melt flow, without prior curing, than that of uncured, non-crosslinked arylene sulfide polymer normally obtained in prior art processes. For example, uncured, non-crosslinked arylene sulfide polymers having a melt flow within the range of 1 to about 700 (determined by the method of ASTM D 1238-70, modified to a temperature of 316.degree. C using a 5kg weight, the value being expressed as g/10 min.), are particularly useful in the production of fibers and molded objects since the usual curing step is obviated. In general, fibers produced from uncured, non-crosslinked arylene sulfide polymers of low melt flow exhibit superior tenacity and less embrittlement on thermal aging than do those of higher melt flow, and objects molded from uncured, non-crosslinked arylene suflide polymers of low melt flow have better impact resistance and better dimensional stability than do those of higher melt flow.
It is therefore an object of this invention to provide a method for producing arylene sulfide polymer that in an uncured, non-crosslinked state has a melt flow within the range of about 1 to about 700. It is also an object of this invention to provide polymers produced by the method of this invention. It is still another object of this invention to provide fibers produced from the polymers produced by the method of this invention.
Other aspects, objects and the various advantages of this invention will become apparent upon reading the specification and its appended claims.